Effect of daily fiber intake on reproductive function: the BioCycle Study

Am J Clin Nutr. 2009 Oct;90(4):1061-9. doi: 10.3945/ajcn.2009.27990. Epub 2009 Aug 19.

Abstract

Background: High-fiber diets have been associated with decreased breast cancer risk, likely mediated by the effect of fiber on lowering circulating estrogen concentrations. The influence of fiber on aspects of reproduction, which include ovulation, has not been well studied in premenopausal women.

Objective: The objective was to determine if fiber consumption is associated with hormone concentrations and incident anovulation in healthy, regularly menstruating women.

Design: The BioCycle Study was a prospective cohort study conducted from 2004 to 2006 that followed 250 women aged 18-44 y for 2 cycles. Dietary fiber consumption was assessed < or =4 times/cycle by using 24-h recall. Outcomes included concentrations of estradiol, progesterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH), which were measured < or =8 times/cycle, and incident anovulation.

Results: Dietary fiber consumption was inversely associated with hormone concentrations (estradiol, progesterone, LH, and FSH; P < 0.05) and positively associated with the risk of anovulation (P = 0.003) by using random-effects models with adjustment for total calories, age, race, and vitamin E intake. Each 5-g/d increase in total fiber intake was associated with a 1.78-fold increased risk (95% CI: 1.11, 2.84) of an anovulatory cycle. The adjusted odds ratio of 5 g fruit fiber/d was 3.05 (95% CI: 1.07, 8.71).

Conclusions: These findings suggest that a diet high in fiber is significantly associated with decreased hormone concentrations and a higher probability of anovulation. Further study of the effect of fiber on reproductive health and of the effect of these intakes in reproductive-aged women is warranted.

Publication types

  • Research Support, N.I.H., Intramural

MeSH terms

  • Adolescent
  • Adult
  • Anovulation / blood
  • Anovulation / etiology*
  • Diet
  • Diet Records
  • Dietary Fiber / administration & dosage
  • Dietary Fiber / adverse effects*
  • Dose-Response Relationship, Drug
  • Estradiol / blood*
  • Female
  • Follicle Stimulating Hormone / blood*
  • Humans
  • Luteinizing Hormone / blood*
  • Progesterone / blood*
  • Prospective Studies
  • Risk Factors
  • Young Adult

Substances

  • Dietary Fiber
  • Progesterone
  • Estradiol
  • Luteinizing Hormone
  • Follicle Stimulating Hormone